Ten rhesus monkeys were subjected to detailed cerebral and cardiac monitoring over a period of 90 minutes following an experimental gunshot wound. Bradycardia, decreased cardiac output, and decreased pulmonary and systemic blood pressures were observed in the presence of normal preloading (right and left atrial pressures) and afterloading (pulmonary and systemic vascular resistances). Defective cardiac output, autoregulation and cerebrovascular resistance were associated with low perfusion pressures, low cerebral blood flow, and low CMRO2.